一种功率因数数字化测量算法的设计与实现

摘要

A digital power factor measurement algorithm was proposed. Power factor was measured by respectively calculating current waveform factor and fundamental shift factor after yielding the digital signal sequence of grid voltage and input current using discrete fourier decomposition method. Finally, a 200 W experiment platform of single-phase power factor correction was build,containing single-phase PFC converter,power analyzer and MATLAB measurement system. The experiment result shows that the relative error is within 1% between the calculated result based on the presented algorithm and measured result based on power analyzer.%提出了一种功率因数数字化测量算法。通过检测电网电压和输入电流得到对应的数字信号序列，并通过傅里叶分解对基波进行提取，分别计算出电流波形系数和基波位移因数，从而得到功率因数。最后搭建了一个200 W的单相功率因数校正PFC( Power Factor Correction)变换器实验平台，该平台由单相PFC变换器，功率因数分析仪和MATLAB测量系统组成。实验结果显示，基于此算法计算出来的结果和利用功率分析仪测出来的功率因数的误差在1%以内。